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dc.contributor.advisorFasel, Hermann F.
dc.contributor.authorKoessler, Jeffrey H.
dc.creatorKoessler, Jeffrey H.
dc.date.accessioned2018-06-18T23:03:39Z
dc.date.available2018-06-18T23:03:39Z
dc.identifier.urihttp://hdl.handle.net/10150/627980
dc.description.abstractDynamic soaring in the atmospheric boundary layer of a vertical variation of horizontal winds over arbitrary terrain offers small unmanned aerial vehicle gliders the ability to greatly expand mission operations while also extending endurance. Wandering albatrosses and other oceanic birds have provided the original evidence of the ability to exploit vertical wind gradients through their long distance circumnavigation flights using periodic maneuvers with cycles of upwind, crosswind, and downwind phases orchestrated to extract sufficient energy from the environment to allow perpetual flight. Dynamic soaring analysis presents additional challenges to the established theories of aerodynamic flight dynamics, due to the presence of wind vector fields that can vary their magnitude and direction in spatial and temporal dimensions. Preserving a consistency with typical flight analysis including static soaring, an air-relative wind-aligned / wind-fixed reference frame is proposed for dynamic soaring analysis, in particular for the computation of kinetic energy. Novel contributions of this present work include a logical progression of seven heuristic assumptions leading to a singular conclusion regarding the appropriate usage of airspeed for kinetic energy computation. Also, a concept of fundamental equivalence between spatial and temporal gradients experienced by a flight vehicle is presented, including the mechanism by which both generate the same accelerating reference frame and apparent dynamic soaring thrust. A novel reverse kinematics simulation is introduced, built on a parametric trajectory definition and analysis via Frenet-Serret equations. A series of dynamic soaring steady-state scenarios are presented and used to amplify the spatial and temporal gradient equivalence concept. The familiar glider sink polar curve is used in two novel ways: first, the curve shift procedures typically employed to account for changes in glider weight for uniform wind flight are proposed as also applicable to account for the apparent weight change during dynamic frame acceleration; second, the sink polar curve is transformed into a sink polar surface representing a family of curves with the additional dimension of weight inflation ratio. These novel insights and observations are intended to provide a solid foundation for present and future dynamic soaring analysis across a spectrum of interdisciplinary research.en_US
dc.language.isoen_USen_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.subjectdynamicen_US
dc.subjectglideren_US
dc.subjectsoaringen_US
dc.subjectuaven_US
dc.titleDynamic Soaring UAV Glidersen_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
thesis.degree.grantorUniversity of Arizonaen_US
thesis.degree.leveldoctoralen_US
dc.contributor.committeememberHead, Kenneth L.
dc.contributor.committeememberLittle, Jesse C.
dc.contributor.committeememberShkarayev, Sergey V.
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineAerospace Engineeringen_US
thesis.degree.namePh.D.en_US
refterms.dateFOA2018-06-18T23:03:39Z


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